Reinforced shipping container

ABSTRACT

A blank foldable to form an edge reinforced box or carton, said blank including a plurality of flaps hingedly connected with the horizontal edges of the end and sidewalls, respectively, for closing the upper or lower end of the box. The invention is characterized in that at least one of the top or bottom end flaps contains a pair of slits that define glue tabs hingedly connected with the adjacent edges of the side flaps, said glue tabs being arranged longitudinally to extend around an edge of the box into sealed engagement with the outer surface of the adjacent end wall, thereby to strengthen and reinforce the box edge.

United States Patent [72] Inventor Roger L. McCulloch Elmhurst, Ill. [2| Appl No 823,738 [22] Filed May 12, 1969 [45] Patented June 22, I97! [73] Assignee Boise Cascade Corporation Boise, Idaho 1 [54] REINFORCED SHIPPING CONTAINER 4 Claims, 14 Drawing Figs.

[52] US. Cl 229/37 R, 229/38, 229/44 [51] Int. Cl .1 865d 5/02 [50] Field of Search 229/37 R, 44 R, 38

[56] References Cited UNITED STATES PATENTS I,223,232 229/37 4/1917 Ash 2,652,970 9/1953 George 229/37 3,007,376 11/1961 Hickin et a]. 229/37X 3,l97,1l0 7/1965 Neuman et al 229/44 X Primary Examiner-David M. Bockenek AttorneyLawrence E. Laubscher ABSTRACT: A blank foldable to form an edge reinforced box or canon, said blank including a plurality of flaps hingedly connected with the horizontal edges of the end and sidewalls, respectively, for closing the upper or lower end of the box. The invention is characterized in that at least one of the top or bottom end flaps contains a pair of slits that define glue tabs hingedly connected with the adjacent edges of the side flaps,

d glue tabs being arranged longitudinally to extend around an edge of the box into sealed engagement with the outer surface of the adjacent end wall, thereby to strengthen and reinforce the box edge.

PATENIEDJU-22191| 3.586.233

INVENTOR Roger L. McCulloch BY XWM 6. WM.

ATTORNEY PATENTEUJUHZZIQYI 43586233 SHEET 2 OF 5 Ion 1 INVENTQR ATTORNEY REINFORCED SHIPPING CONTAINER It is generally known in, the patented prior art to provide cardboard boxes having glue tabs for reinforcing the box edges. Examples of such known boxes are presented in the patents to Tress et al. No. 3,294,308, Mosse et al. No. 3,110,433, Smith No. 3,357,629 and Hickin et al. No. 3,007,376.

Certain structural considerations must be kept in mind in designing a blank for forming cardboard boxes or cartons. First, the blank must be so designed that waste is kept to a minimum. Secondly, the flaps must be so arranged that adhesive may be readily applied thereto for rigidly joining the panels to seal the box. Thirdly, the edges must be reinforced in such a manner that they are not only strong enough to assist in sealing the closure flaps to the walls of the receptacle, but also to strengthen the receptacle against the application of longitudinal stresses thereto. The present invention was developed to provide an improved box blank construction that avoids the above and other drawbacks of the patented prior art.

Accordingly, the primary object of the present invention is to provide an. improved waste-free blank construction for forming a rectangular edge-reinforced box or carton, said blank including end and sidewall sections having hingedly connected to at least one edge thereof closure flaps for par tially closing at least one end of the box. The invention is characterized in that the sidewall closure flaps carry at adjacent ends a pair of glue tabs, respectively, that extend around a common edge of the end wall into contiguous engagement with the outer surface thereof. Since the widths of the flaps are no greater than half the length of the end sections, the side flaps are firmly locked in place by their direct adhesion to the end wall flaps, and by the adhesion of the glue flaps to the end walls.

In accordance with a more specific object of the invention, the glue or tape joint for initially forming the walls into an open-ended rectangular configuration is displaced from a vertical edge to a central portion of either an end wall or a sidewall of the box, thereby assuring that unitary strong hinge lines define the comers of the box.

In accordance with another object of the invention, the width of each of the top flaps is somewhat less than one-half the length of the corresponding end wall, whereby a gap is formed between the adjacent edges of the side flaps when the box is in its finally formed condition; consequently, an additional reduction in blank material is achieved while assuring a strong edge connection between the top closure flaps and the other box parts.

Another object of the invention is to provide a blank that may be at least partially glued by means of a continuous roller applicator, characterized by the provision of projections on at least one of the glue tabs for covering the normally exposed extremities of a roller-applied glue area.

Other objects and advantages of the invention will become apparent from a study of the following specification, when considered in conjunction with the accompanying drawing, in which:

FIG. 1 illustrates a first blank embodiment for forming a rectangular box or carton;

FIG. 2 is perspective view illustrating the assembly of the blank of FIG. 1 to form a rectangular box;

FIG. 3 is a perspective view of the completed edge-reinforced box formed from the blank of FIG. I;

FIGS. 4 and 5 are alternate blank embodiments wherein the glue and tape joints between the folded wall sections respectively, are contained in one side and one end, respectively, of the box;

FIG. 6 illustrates a further blank embodiment wherein the tape joint is contained in an end panel of the box;

FIG. 7 illustrates another box embodiment wherein a gap is formed between the adjacent edges of the sidewall top flaps;

FIG. 8 illustrates an intermediate glueing step in the construction of a box from the blank of FIG. 1;

FIGS. 9Il are modifications of the blank embodiment of FIG. I;

FIG. 12 illustrates an intermediate gluing step in the construction of a box from the blank of FIG. 9; and

FIGS. 13 and I4 are detailed perspective views of the corner assemblies of the boxes formed by the folded blanks of FIGS. 9 and 10, respectively.

Referring to FIG. I, the paperboard or cardboard blank includes, in succession, a first sidewall 2, a first end wall 4, a second sidewall 6, and a second end wall 8. To the bottom edges of these walls are hingedly connected the first side bottom closure flap 10, first end bottom flap 12, second side bottom flap 14 and second end flap 16. To the upper edges of the walls are hingedly connected the first side upper flap 18, first end upper flap 20, second upperside flap 22 and second upper end flap 24.

In accordance with the present invention, the end flaps contain slits 30 that define glue tabs 10a, 14a, 14b, 18a, 22a, and 22!) that are hingedly connected with the corresponding ends of the lower and upper closure flaps 10, 14, I8 and 22 respectively. Three additional glue flaps 2a, 10b and 18b are hingedly connected with the three edges of panels 2, 10 and 18, respectively. Each slit 30 includes a first portion 30a that extends at an angle of about 45 from the junction between the corresponding flaps and walls, and a second portion 30b that extends parallel to the glue tab hinge line defined thereby. The adjacent edges of the three additional glue tabs 2a, 10b, and 18b are similarly beveled at an angle of about 45.

The widths of the closure flaps are equal to generally onehalf the length of the end walls, whereby when the adhesive 34 is applied to the flap and tab surfaces as shown in FIG. 2 and the box is completely formed as shown in FIG. 3, the nine glue tabs extend from their respective flaps around the edges of the end walls into sealed engagement with the outer surfaces thereof. The edges of the box are thereby strengthened and reinforced to withstand longitudinal load thrust developed by the container contents 36 (such as cans or the like) as shown by the arrow 38. Thus, each flap is secured both to the end flaps overlapped thereby and also, by means of the glue tabs, to the end walls, of the box.

In the embodiment of FIGS. 1-3, the joint between the wall sections 2 and 8 at one vertical edge of the box is bridged and closed by the hingedly connected glue tab 2a. Referring now to the embodiment of FIG. 4, the blank is so designed that the glue joint is displaced from the vertical corner edge to the center of the side panel. To this end, one sidewall of the carton consists of two sections 102, 140 the combined length of which is slightly greater than the length of the other side wall 106, thereby to provide the glue joint overlap. It will be seen that this embodiment affords the further advantage that there is no manufacturing waste and that following assembly, the upper and lower edges of the end walls are completely protected and reinforced by the glue tabs 118, 1220, 122b, 142a, a, 114a, ll4b and 144a.

1n the embodiment of FIG. 5, the glue joint is contained on an end wall of the box, said end wall comprising the two sections 208, 240 having a combined length that is slightly greater than that of the end wall 204 to define the glue joint overlap. Again, the upper and lower edges of the fully assembled box are reinforced and strengthened by the glue tabs 218b, 218a, 222a, 222b, 210b, 2100, 214a and 2l4b. In the modification of FIG. 6, the sum of the lengths of the end wall parts 308 and 340 is generally equal to the length of the end wall 304 whereby a taped seam butt joint isdefined. It is apparent of course, that in the alternative, the panel lengths may be proportioned to afford a taped butt joint within a length dimenmen.

In each of the blank embodiments of FIGS. 1, 4, 5 and 6, the flap width generally equals one-half the length of the end wall, whereby the upper and lower pairs of flaps abut when in the closed position, as shown in FIG. 3. In order to conserve box material for the packaging of certain products, such as cans, the widths of the flaps are reduced to somewhat less than onehalf the width of the end walls, whereby a gap-400 is formed between the flaps, as shown in FIG. 7. Owing to the glueing of the tabs to the outer surfaces of the end walls, the reinforcement of the box edges and the strength and durability of the resultant assembly is greatly improved.

It is apparent that the joining of the side and end walls (by glueing, taping or stitching) may be performed either at the plant of the box manufacturer, or at the point of ultimate use.

Assume now that during the plant manufacture of a box from the blank of FIG. I, in order to effect an intermediate glueing step the blank'is folded in half to the configuration of FIG. 8 for the application of glue to the tab 2a and the corresponding glue area 34b on the outer surface of the end wall 8. in the case of a box that is to be filled and sealed at a later time, it is important that this glueing of the area 34b and the tab 20 be carefully perfonned (generally by a conventional skip" glueing technique) to assure that the glue is contained in the desired areas, so that the adhesive will not inadvertently be applied to the adjacent areas of the box which are to be maintained dry. Otherwise, when the tab 2a of FIG. 8 is folded into engagement with end wall 8 and a plurality of such blanks are stacked for storage or transport, there would be an undesirable joining of the blanks by the noncontained adhesive.

ln order to avoid the necessity of skip glueing, the modification of FIG. 9 was developed wherein the portions 460 are removed from end flaps 416 and 424. Thus, when the blank of FIG. 9 is folded to the configuration of FIG. 12, the continuous glue area-434b may be readily applied by a conventional roller applicator.

In order to further assure that there will be no sticking between a plurality of stacked blanks which have been partially assembled by the intennediate glueing step shown in FIGS. 8 and 12, the blank modifications of FIGS. 10 and 11 have been developed. Referring to FIG. 10, it will be seen that the additional glue tabs l0b and 518b on the lower and upper sidewall flaps 510 and 518 contain angularly arranged slits 550 that define .projections 5020' on the upper and lower ends of the glue tab 502a. These angular projections are adapted to be folded into engagement with corresponding portions defined on end wall flaps 516 and 524 by the removal of the portions 560 as shown in FIG. 13. More particularly, these projections serve to cover the upper and lower extremities of the glue area 434b in FIG. 12, which extremities, in that embodiment, are not covered by the folded glue flap 402a.

In the modification of F lG. 11, the lower and upper sidewall flaps 610 and 618 contain a pair of right angled cuts 650 that define square projections 6020 on the upper and lower ends of the glue tab 6020'. These projections are adapted to be folded to cover the corresponding portions of flaps 616 and 624 defined by the removal of portions 660, as shown in F lG. 14. Thus, the upper and lower extremities of the glue area 634b are covered by the projections 602a, whereby the possibility of sticking together of the blanks as avoided. ln this modification, the square projections afford a greater area, and

there is less chance of delamination when the inner flap is folded in.

What I claim is: l. A unitary rectangular blank foldable to form a reinforced receptacle, comprising a series of five successive hingedly connected vertical sections the second and fourth of which have the same width and the first and fifth of which have widths the sum of which is generally equal to that of said third section, whereby when said sections are folded to define a rectangular configuration, said first and fifth wall sections are contained in a common vertical plane with their free edges adjacent each other to define one wall of said receptacle, one opposed pair of walls of said receptacle being end walls having a width that is less than that of the other pair of walls; a plurality of top and bottom flaps hingedly connected with the horizontal upper and lower edges of each of said wall sections, respectively, the widths of said flaps corresponding with the widths of the walls to which they are connected, respectively, the height of said flaps being no greater than one half the width of said end walls, at least one of the top and bottom flaps connected with one of said end walls containing adjacent each vertical edge thereof a vertical slit defining a tab hingedly connected with the adjacent edge of the corresponding side top and bottom flaps, respectively;

said end top and bottom flaps being foldable inwardly to horizontal positions between the upper and lower edges of said sidewalls, respectively, said side top and bottom flaps being foldable to horizontal positions overlapping said end top and bottom flaps, respectively, each of the tabs carried by said side flaps being foldable around the adjacent end wall edge to external reinforcing positions for rigid securement against the outer surface of the lower edge portion of the adjacent end wall, whereby each of the vertical corners of the receptacle consists of a unitary hinge line and the end walls of said receptacle are reinforced at their upper and lower edges by said glue tabs.

2. A blank as defined in claim 1, wherein said second and fourth sections have a width less than that of said third section, thereby defining end walls of said receptacle, whereby the joint between the edges of said first and fifth sections is a sidewall center joint.

3. A blank as defined in claim 1, wherein said second and fourth sections have a width that is greater than that of said third section, thereby defining sidewalls of said receptacle, whereby the joint between the edges of said first and fifth sec tions is an end wall center joint.

4. A blank as defined in claim 1, wherein the sum of the widths of said first and fifth walls equals that of said third wall, whereby the joint between the adjacent edges of said first and fifth walls is a buttjoint. 

1. A unitary rectangular blank foldable to form a reinforced receptacle, comprising a series of five successive hingedly connected vertical sections the second and fourth of which have the same width and the first and fifth of which have widths the sum of which is generally equal to that of said third section, whereby when said sections are folded to define a rectangular configuration, said first and fifth wall sections are contained in a common vertical plane with their free edges adjacent each other to define one wall of said receptacle, one opposed pair of walls of said receptacle being end walls having a width that is less than that of the other pair of walls; a plurality of top and bottom flaps hingedly connected with the horizontal upper and lower edges of each of said wall sections, respectively, the widths of said flaps corresponding with the widths of the walls to which they are connected, respectively, the height of said flaps being no greater than one half the width of said end walls, at least one of the top and bottom flaps connected with one of said end walls containing adjacent each vertical edge thereof a vertical slit defining a tab hingedly connected with the adjacent edge of the corresponding side top and bottom flaps, respectively; said end top and bottom flaps being foldable inwardly to horizontal positions between the upper and lower edges of said sidewalls, respectively, said side top and bottom flaps being foldable to horizontal positions overlapping said end top and bottom flaps, respectively, each of the tabs carried by said side flaps being foldable around the adjacent end wall edge to external reinforcing positions for rigid securement against the outer surface of the lower edge portion of the adjacent end wall, whereby each of the vertical corners of the receptacle consists of a unitary hinge line and the end walls of said receptacle are reinforced at their upper and lower edges by said glue tabs.
 2. A blank as defined in claim 1, wherein said second and fourth sections have a width less than that of said third section, thereby defining end walls of said receptacle, whereby the joint between the edges of said first and fifth sections is a sidewall center joint.
 3. A blank as defined in claim 1, wherein said second and fourth sections have a width that is greater than that of said third section, thereby defining sidewalls of said receptacle, whereby the joint between the edges of said first and fifth sections is an end wall center joint.
 4. A blank as defined in claim 1, wherein the sum of the widths of said first and fifth walls equals that of said third wall, whereby the joint between the adjacent edges of said first and fifth walls is a butt joint. 